Pressure pad box taping machine and method



L.. GIDGE 3,505,774

PRESSURE PAD BOX TAPING MACHINE AND METHOD 3 Sheets-Sheet 1 April 14, 1970 Filed oct. 23. 1967 April 14, 1970 3 Sheets-Sheet 2 Filed Oct. 25, 1967 INVENTOR. LESTER G I DGE p #Ta/MLM ATTORNEYS l.. GIDGE 3,505,774

PRESSURE PAD BOX TAPING MACHINE AND METHOD,

April 14, 1970 3 Smets-sheet a Filed 001;. 25, 1967 INVENTOR. LESTER GIDGE muy *Pa/:Aon

ATTORNEYS United States Patent O 3,505,774 PRESSURE PAD BOX TAPING MACHINE AND METHOD Lester Gidge, 61 Linwood St., Nashua, N.H. 03060 Filed Oct. 23, 1967, Ser. No. 677,404 Int. Cl. B651 7/20, 6]/00; B31b 1/72 U.S. Cl. 53-14 14 Claims ABSTRACT F THE DISCLOSURE An automatic top flap closing and top and bottom taping machine of the type having a conveyor moving each successive random-sized, carton iirst to a measuring and top ap folding station, where a singlehead descends to sense size, fold flaps, and adjust to taping requirements, and then through a taping zone where the carton is held closed as moist tape is applied along the front wall, along top and bottom walls, and along rear wall of the carton. The trailing flap folder adjusts to cartons of unusual length, a backer plate extends under the infolded upper side flaps during taping for proper adhesion and tape is applied by at yieldable pad pressure for a prolonged period, rather than by roller nip pressure, to assure a firm sealing. The adhesive on the tape is physically upset and grooved during moistening by nip pressure against a double helix grooved `wetting roll to speed wetting and assure spreading of the adhesive for a firm seal.

BACKGROUND This invention relates to apparatus for automatically closing the top aps of random sized cartons which have been erected from at tubular condition, the bottom flaps closed but not sealed and lled with products which may be cans, boxes, fragile articles, or loose material. When such cartons are of uniform size, operating on the same presents few problems and folding and taping can often be accomplished during a continuous flow along a path.

However, with random sized boxes, it has long been the custom, as exemplied in U.S. Patents to Keely, No. 2,721,669, of Oct. 25, 1955', No. 2,999,342, of Sept. l2, 1961, No. 3,045,402, of Iuly 24, 1962, and No. 3,052,072, of Sept. 4, 1962, to advance each random sized carton step-by-step, through first a measuring station, then a folding station, and then a taping zone or station, each station having an elevator head for performing the various functions. In view of the considerable floor space occupied by such machines and the complexity thereof, there have come onto the market fully automatic tapers for random sized cartons, which occupy less floor space and have only a single elevatable head which contains top flap folding mechanism in a combined measuring and folding station, and which contains top tape applying means in a taping zone. Exemplary of such machines is the Padlocker No. 200 Random made by Padlocker Machinery Company Division of Atlantic Gummed Paper Corporation of Brooklyn, N.Y., and the Bantam Top and Bottom Tape Sealer made by General Corrugated Machinery Co., Inc. of Palisades Park, NJ.

All of the above machines use toggle mounted pressure rolls for applying the moist tape on the leading wall of the carton, then along the top and bottom, and then on the trailing wall of the carton, and the momentary tangential roll contact has been found too short a period to assure that the glue penetrates into the carton and sets properly. Thus with pressure roll tape applying, the taped cartons sometimes become unsealed, the tape may have no adherence in critical locations, and the sealed cartons may not be up to commercially acceptable standards. Similarly depending on the adhesive used on the tape,

3,505,774 Patented Apr. 14, 1970 ice which normally is the type requiring moistening to adhere, it has been found that in high speed operation, the glue may not be suiciently wet to secure a good grip on the carton, that the rollers jump oif the corners of the box in rounding the same, and that roll contact along the unbacked, yieldable, top of the carton creates insufficient pressure to achieve a firm seal.

In the machine and method of this invention, a short floor length, single head apparatus is provided, in which the moist tape is applied by ilat, resilient faced pressure pads which travel along with the leading and trailing walls of each carton in the taping zone while applying constant, controlled pressure for a prolonged period of time to assure penetration and thorough sealing. In addition, the leading wall pressure pads assume an inclined position at the end of their path, so that the top and bottom stretches of the tape are wiped into a firm unwrinkled seal as the carton is pushed along the pads. To further seal the top and bottom stretches, a fixed roll and a yieldable roll form a nip through which the carton is pushed to roll the top and bottom tape stretches before they reach the inclined pads. To assure moistening of the adhesive on the tape, the tape is fed through the nip of a helically ribbed and grooved wetting roll and a resiliently mounted pressure roll to physically upset the dry adhesive into line grooves which receive the wetting liquid while spreading the wet adhesive.

In the machines of the prior art, a barrier has been used to infold the leading top flap, twisted fold bars have been used to infold the top side flaps, and an arcuately movable folder arm has been used to infold the trailing top ilap. The length of carton foldable in the :machine has been limited by the arcuate path of the trailing flap folder, since it would not strike the trailing flap of an unusually long carton. In this invention, the trailing ilap folder normally swings in an arc which will infold the trailing top flap of a carton of predetermined length, such as twenty inches, but if the machine senses a carton of, for example, thirty inch length, the trailing flap folder carriage moves rearwardly automatically to an alternate position for properly folding the flap.

DRAWING In the drawings:

FIGURE 1 is a somewhat schematic side elevation, in section, showing a machine constructed in accordance with the invention;

FIGURE 2 is a schematic plan view thereof, partly in section on line 2-2 of. FIGURE l;

FIGURE 3 is a schematic end view thereof, partly in section;

FIGURE 4 is an enlarged, perspective view of the tape moistening and stripper means;

FIGURE 5 is a fragmentary side elevation of the trailing ilap folder in alternate position; and

FIGURE 6 is an enlarged fragmentary side elevation showing the sensing arm extension serving as a backer plate in the taping zone.

DESCRIPTION OF THE DRAWINGS As shown in the drawings, 30 designates a fully automatic machine, constructed in accordance with the invention, for measuring, closing and tape sealing a plurality of random sized cartons 31, individually and successively. Machine 30 includes a frame 32, a carton path or line 33, a carton measuring and top flap folding station 34, a top and bottom tape applying zone 35, and a Single vertically movable head 36 for performing the operations on the top of the carton.

Each carton 31 includes the leading wall 38, trailing wall 39, side wall, such as 40, leading top ap 41, trailing top ap 42, top side flaps such as 43, corresponding bottom flaps which are infolded but unsealed, the lower portion 44 of the trailing wall and the upper edge 45 of the leading wall. It will be understood that each carton 31 has been erected from a flat tubular lblank, the bottom flaps infolded but unsealed, the carton filled and then delivered in random sizes by an infeed conveyor 46 of any well known type until each successive endmost carton reaches the upstanding infeed gate 47 at the entrance of station 34. The end flaps 41 and 42 are in the position shown so that they may be infolded under the side aps 43.

The endmost carton 31 trips the gate 47, causing the gate to temporarily drop below the carton path 33 and energizing motor 48 and power train 49, to rotate feed rolls 50 and drive endless conveyor apron 51 to advance the carton up to the second gate 52. The photoswitch 60 halts the apron motor with carton 31 at the station 34 and also brings in the side rail bars 72 and 73, to be described, and causes the head 36 to descend. The infeed gate 47 rises, when cleared by the trailing edge of the carton to stop the next successive endmost carton 31 on infeed conveyor 46, until the preceding box has cleared the limit switch 53 at the end of tape applying zone 35. Apron 51 is trained on rolls 54 and 55 and is coextensive with the station 34, the cartons being supported on horizontal plates 56 and 57 in zone 35, which are spaced apart at 79 and co-planar with carton line 33. A pair of endless chains 58 and 59, one on each opposite side of the machine 30, are each trained around sprockets 61, 62, 63 and 64, and tension sprocket 65, with sprocket 61 driving roll 54 and the sprocket 62 driven by power train 66 from motorized variable speed gear reduction unit 67.

Pusher means 69 is provided in the form of a pair of bars 70 and 71 mounted transversely across chains 58 and 59, so that when trailing flap folder 103 trips switch 68, the carton then in station 34 is engaged in the lower trailing wall portion 44 and pushed through the taping zone sliding on plates 56 and 57 to positively overcome the resistance of the pressure pads and pressure rolls therein.

The photoswitch 60 not only halts the conveyor means 51 but also actuates a pair of side guides, or rails, 72 and 73, to move inwardly to center the carton 31 halted at the station. Each guide, such as 72, is coextensive in length with the station 34 and the zone 35 and mounted on a pair of pantograph lever arms 74 and 75, pivoted to frame 32 at 76 and 77 and having a pivoted connecting bar 78. The side guide bars 72 and 73 are actuated by a pair of connecting rods 80 and 81, pivotally connected to the piston 82 of an air cylinder 83.

'Ille vertically movable head 36 is normally poised at the upper limit of three posts 85, 86 and -87, to which position it is moved by the upstanding air cylinder and piston 88, and hydraulically locked in position by the hydraulic cylinder and piston 89. Upon the breaking of the beam of switch 60, the head 36 is unlocked and descends by gravity with the carton height-sensing lever 91 extending downwardly at an incline from its pivot 92 on the depending frame piece 93. Upon engaging the leading upper edge 45 of the carton 31, the lever 91 is lifted substantially to horizontal position, thereby sensing the height of the carton and actuating the valves of hydraulic lock 89 to halt the descent of head 36 at the correct height for the carton. The top leading ap 41 is down-folded by engagement with the height-sensing lever 91, which serves the purpose of a front flap folder. The trailing flap folder 103 is actuated by switch 231 which is closed by the link of arm 127.

Trailing top ap folding means 95 includes the carriage 96 pivotally mounted on pantograph arms 97 and 98 supported in frame pieces 99, so that the carriage 9-6 is movable between its normal position shown in FIGURE l, for a shorter carton, to the alternate position shown in FIGURE 5, for a longer carton. A limit switch 100 mounted on one of the side guide rails 72 or 73 is tripped by the rear edge of a carton longer than, for example, twenty inches, and causes carriage 96 to move to its alternate rearward position by means of piston 101 and fluid cylinder 102. The trailing flap folder 103 is pivoted at 104 to frame pieces 99 and pivotally connected at 105 to piston rod 106 of cylinder 107 pivoted to the carriage 96 at 108, so that the folder describes an arcuate path of folding as shown by the dotted arrow, when switch 60 is closed.

A pair of top side flap folders 110 and 111 are mounted on head 36, each including a longitudinally extending bar 112 laterally slidable on transverse rods 113 and 114, each rod having a shaped folder plate 115 to infold a side flap. The bars 112 are each connected at 116 and 117 to an endless cable 118 trained on sheaves 119 and 120 so that motion of one is imparted to the other. A piston rod 121, actuated by a fluid cylinder 122 actuates the folder 110 when trailing flap folder 103 strikes limit switch 68 and a hydraulic lock valve on cylinder 122 is actuated when a contact button 123 on one of the folders strikes the side wall of the carton 31 to avoid damaging the contents.

The frame piece 93 of leading flap folder 91 and the trailing flap folder 103 each are of thin reduced cross ction at 125 and 126, so that the top side aps 43 may be infolded over the flaps 41 and 42 with the longitudinal edges of the side flaps engaging the portions 125 and- 126 and so that the carton may be pushed in the direction of feed with the leading and trailing folders in place.

Immediately after sensing height and causing the descent of the head, the sensing lever 91 is automatically locked in horizontal position so that the elongated extension 127 thereof may serve as a backer plate. It should be noted that the extension 127 is sufficiently long to permit its tip 128 to reach well into the taping zone 35 and nearly up to the tape feed location. Lever 91 is so locked by the piston 129 and cylinder 130 carried on head 36.

A safety switch 132 is mounted on head 36 in the path of anything projecting above the normal level of the top of the carton, which, when tripped, stops the entire machine. A carton at the folding and measuring station must therefore be ready to pass through the taping zone without damage when switch 68 starts the pusher bar chain motor 67 and the pusher bar 70 or 71 closes switch 131 to lower gate 52 and start the tape feed motor 149. Motor 149 does not cause tape feed at this time because the tape feed nip rolls 146 and 147 are open.

Moist adhesive tape supply means 133 is mounted in the taping zone 35, in the form of an upper tape feed assembly 134 and upper tape moistening assembly 135 in head 36 and substantially identical lower tape feed assembly 136 and lower tape moistening assembly 137 mounted in frame 32 below the level of the carton path 33.

Each tape feed assembly 134 or 136 includes a tape roll supporting disc 138, rotatably mounted at 139 and inclined at an' angle of about sixty degrees from the horizontal to prevent the undesired telescoping of the tape roll 140, which may occur when the roll is vertical. A brake shoe 141 engages the rim of disc 138 and is carried by an L shaped arm 142 having a tape guide rod 143 at the other end thereof. When the tape 144 is under feed tension, guide rod 143 moves to release the brake and, when tension is released, brake shoe 141 re-engages the rim to halt over-running of the roll. The adhesive coated tape 144 is threaded through .a bifurcated guide 145 and through the nip of a pair of feed rolls 146 and 147, thence to a cutter 148, the feed rolls being driven by motor 149.

Each tape moistening assembly or 137 includes a receptacle 150 having a water inlet 151 and a partially immersed water applicator, or wetting roll, 152, joumalled in the upper forward wall of the receptacle so that the circumferential surface 153 tangentially engages the dry adhesive coated layer 154 on tape 144 (FIGURE 4). The

roll surface 153 is finely ribbed and grooved at 155 in double helix configuration and forms a pressure nip 156 with a smooth faced pressure roll 157 which is spring biased to resiliently press tape 144 against the helical ribbed face 153 with suiicient predetermined pressure to upset and physically deform the adhesive layer 154 into ribbed and grooved configuration. Thus the double helix face 153 spreads the adhesive, from the centre outwardly while increasing the area of Contact of the water with the adhesive by filling the grooves and a rapid, thorough wetting takes place despite the speed of advance of the tape through the nip 156. The clearance of the nip 156 is preferably equal to the thickness of the tape 14.4 without its layer of adhesive 154 so that the solid adhesive layer is forced into ribs and grooves in order to pass through the tight nip 156.

Stripper belt means 160 is mounted on each tape moistening assembly 135 and 137 and includes a pair of O section endless belts 161 and 162 of rubber or the like, each trained around sheaves 163, and each having a stretch 164 or 165 advancing in the direction of feed away from the surface 153 toward the carton path 33 to assure the stripping of the highly adhesive ribbed and grooved tape 144 while guiding the tape in the desired direction. The water in receptacle 150 is heated to increase penetration and wetting.

The upper tape feed and moistening assemblies include a pressure roll 168, rotatable on a fixed axis 169 with its smooth circumferential carton-contacting face 170 projecting below the lower face of head 36 a predetermined distance such as an eighth or a quarter of an inch. The lower tape feed and moistening assemblies include a similar pressure roll 171 resiliently mounted 0n a movable axis 172 below the carton path 33 but having its circumferential face 173 also projecting slightly into the carton path to engage the bottom of the carton. The two pressure rolls 168 and 171 thus form a pressure nip through which the carton must pass, the nip normally being of slightly less clearance than the height of the carton 31, but being resiliently expandable to press firmly against the top and bottom stretches of tape 144 as the carton advances through zone 35. Preferably guide belts, or bars, such as 175 and 176 are associated with rolls 157, 168 and 171 to guide and support the non-adhesive face of the tape in the direction of feed toward carton path 33.

The prolonged pressure applying means 180 of the invention includes a top, leading-wall, pressure pad assembly 181, a top, trailing-wall pressure pad assembly 182, both mounted in head 36, a bottom, leading-wall, pressure pad assembly 183, and a bottom, trailing-wall, pressure pad assembly 184, both mounted in the lower portion of machine 20. The assemblies 181 and 182 are substantially identical with assemblies 183 and 184, but inverted. Each leading wall pressure pad assembly 181 or 183 includes a cam track 185 extending longitudinally along carton path 33 in which a cam follower roller carriage 186 is movable, there being an arm 187 pivoted at 188 and connected to the carriage by a pivoted link 189 and a piston rod 190 and spring cylinder 191 for controlling the advance of the carriage 186. Mounted on carriage 186 and normally upstanding vertically in the path of the leading wall of carton 31, is a plate 192 covered with a resilient flat pad 193, for example of soft rubber, the pad 193 being just in rear of the strip of tape 144 being fed by the moist adhesive tape supply means 133. The 'advancing carton 31. pushes the upper and lower pads such as 193 in front of it as it proceeds through zone 35, against the predetermined resistance of the air, or coil spring, pressed piston rod 190 so that the moist adhesive is under constant flatwise pressure for the length of travel of carriage 186 to secure a firm grip and seal on the leading wall of the carton. At the end of cam track 185 a cam recess permits the plate 192 and pad 193 to pivot nearly out of the path of the carton but supports the pad at a slight incline so that the top tape stretch 216 and bottom tape stretch 217 applied along the top and bottom of the carton is resiliently pressed and wiped as the carton advances `between the pair of nearly recumbent pads such as 193. Upon passage of the trailing edge of carton 31, beyond the pads 193, the pressure applying mechanism 191 returns the pads such as 193 of upper assembly 181 and lower assembly 183 to normal position, the projection 194 of the cam track causing the two roller trailer portion 195 of carriage 186 to resume its normal position.

Each trailing wall pressure pad assembly 182 and 184 includes a cam track 197 extending along carton path 33 with a roller cam follower carriage 198 movable therein, the two wheel trailer portion 199 normally being housed in cam recess 200, so that the plate 201 and soft rubber pad 202 are recumbent and out of the path of the carton 31 passing thereby. As soon as the pusher bar means 69 has moved carton 31 along the path 33 beyond the recumbent top and bottom pads 202, the fluid cylinder 203 and piston rod 2'04 push the lever 205, pivoted at 188, in the direction of advance of the carton, so that pivoted link 207 advances the carriage 198 to raise the pads 202 up into the path and against the trailing wall of the carton. The trailing pads thus apply atwise constant pressure on the tape 144 extending along the trailing wall to assure a firm seal grip and penetration until the carton clears the end of cam track 197. The trailing pads are then returned to recumbent position ready for the next carton.

Stop means 210 in the form of a lug 211 is mounted on the lower trailing wall plate 201 arranged to strike the pusher bar 70 or 71 so that regardless of pressure on the plate it cannot overrun the bar and tend 'to prematurely eject the carton from zone 3S. The lower plate 201 is connected by a exible rod, or wire, 212, such as a Bowden wire, to the upper trailing wall plate 201 to cause the upper plate to also be restrained from prematurely ejecting the carton.

A limit switch 213 is located between the support plates 56 and 57 at the entrance of taping zone 35 and extends slightly above the level of carton path 33. When the leading lower edge of a carton 31 being pushed from station 34 into zone 35 strikes switch 213, the switch signals the tape supply means 133 to close the nip of the feed rolls 146 and 147 to commence feeding an upper and a lower moist tape 144 so that the carton Iencounters about a six inch depending tape stretch 214 and about a six inch upstanding tape stretch 215, each in advance of the respective leading wall pressure pads. Switch 213 is held down by the carton, to sense the length thereof and when the trailing edge of the carton clears switch 213, the switch rises to cause the opening of nip rolls 146 and 147 of tape supply means 133. A switch 158 in the path of the opening nip rolls actuates tape cutters 148 to cut the exact length of tape needed for the configuration of the carton. The opening of the nip of the tape feed rolls 146 and 147 relieves tension on the tape and actuates the supply disc brake shoes 141. Bar 70 or 71 strikes a switch 159 to cause the trailing wall pressure pads to move up and apply pressure on the rear carton Wall.

As shown in FIGURE 6, a fixed curved guide 230, on head 36 is in the path of the upper edge 45 of each carton and just above the horizontal extension 127 of sensing arm 91, so that the top side aps 43 are compressed downwardly therebetween and directed downwardly to pass under the pressure roll 168 and into the nip of rolls 168 and 171. The side flaps are thus supported from below proximate the area of tape application, the backing effect of the extension 127, together with the normal rigidity of the corrugated cardboard of the carton, assuring a firm tape application and seal.

The switch 53 is engaged by a protuberance on the pusher bar chains to signal that the particular carton 31 has left the taping zone 35, whereupon the head 36 is lifted to its normal poised position and the next carton 31 is moved into the measuring and folding station 34.

7 Switch 53 also reactivates gate 47 to receive the next carton.

After striking switch 159 to actuate the lower trailing wall pads, each bar 70, or 71, then strikes switch 220 which releases the locking circuit of the height-sensing lever 91, opens the side rail guide bars 72 and 73, opens the top side ap folders 110 and 111, and releases the trailing flap folder 103 to return to normal position.

A switch 221 in the path of the pusher bars 70 and 71 de-energizes the pusher bar motor 67.

What is claimed is:

1, In a fully automatic machine for closing the top aps and for tape sealing the top and bottom flaps of a plurality of random sized, erected, lled cartons advancing individually and successively along a path to a measuring and top ap folding station and then along a top and bottom tape applying zone, said machine having a single vertically movable head extending above said path for measuring carton height and operating on the top of each carton, the combination of top flap folding means on said head at said station for closing the leading, trailing and top side flaps of each said carton;

moist adhesive tape supply means in said taping zone for delivering a predetermined length of moist tape for application to the leading wall, top and bottomside flaps and trailing wall of each carton advancing through said zone; and

prolonged pressure applying means in said taping zone,

including top and bottom leading and trailing flat, resilient pressure pads, means for advancing said at pads with each carton in said zone, each in intimate, prolonged, at-wise pressure contact on the moist tape applied to one of said leading or trailing walls for a predetermined portion of said path to permit the moist adhesive on said tape to secure a firm grip thereon, and means for then positioning said leading pads to secure a wiping contact between said leading wall pressure pads and the tape applied to the top and bottom side aps of said cartons as each carton continues its advance for firmly sealing the same.

2. A fully automatic machine as specified in claim 1 wherein said top flap folding means includes a carriage, a trailing tlap folder pivoted on said carriage, means on said carriage for moving said folder in a predetermined arcuate path to infold the trailing flap of a carton of predetermined length, and means for automatically moving said entire carriage rearwardly, upon the arrival of a carton of greater than predetermined length at said station, to conform said arcuate path to the location of the trailing ap on said carton.

3. A fully automatic machine as speciiied in claim 1 wherein said moist adhesive tape supply means includes a pair of substantially identical tape feed assemblies, one on said head and the other below said path on said machine, each said tape feed assembly including an inclined, rotatable disc supporting a tape roll to prevent telescoping of said roll, brake means operable on said rotatable disc and a tape guide rod movably mounted on said assembly and operably connected to said brake means,

whereby tension of extraction on tape trained around said rod opens said brake means and release of said tension closes said brake means to halt rotation of said disc.

4. A fully automatic machine as specified in claim 1 wherein said moist adhesive tape supply means includes a pair of substantially identical tape moistening assemblies, one on said head and the other belo-w said path on said machine, each said tape moistening 10 wherein each of said moistening assembly includes stripper belt means including a pair of endless belt stretches ex'- tending along the path of the moist face of said tape, in rear of said wetting roll to prevent wind up on said wetting roll while guiding the free terminal tip of said tape on said path. 6. A fully automatic machine as specified in claim 1 wherein said prolonged pressure applying means includes an upper pair of cam tracks and roller follower carriages in said head and a lower pair of cam tracks and roller follower carriages below said path in said machine, one carriage of each pair having one of said leading pads mounted thereon and the other carriage of each pair having one of said trailing pads mounted thereon, said cam tracks maintaining said leading pads in at pressure contact with the leading wall of an advancing carton and then moving said leading pads out of the carton path and guiding said trailing pads from a position out of said carton path to a flat pressure contact position against the trailing Wall of said advancing carton, both for a substantial length of said Zone. 7. A fully automatic machine as specied in claim 6 wherein said means for advancing said leading pads includes uid piston and cylinder mechanism for resisting the advance of said leading pads with a predetermined yielding pressure and said means for advancing said trailing pads includes fluid piston and cylinder mechnism for advancing said leading pads at greater speed than the speed of said carton to thereby apply constant pressure on the carton rear wall in the direction of carton advance. 8. A fully automatic machine as specilied in claim 1 plus endless chain actuated transverse bar pusher means operable on the lower rear wall of each carton in said taping zone to push the carton therethrough despite the tape applying pressure applied to said carton, and stop means on said lower traling pad operable to engage said pusher bar to prevent said trailing pads from exerting undue pressure on the trailing wall of said carton during passage through said zone. 9. A fully automatic machine as specified in claim 8 plus flexible rod connection means extending between said lower trailing pressure pad and the corresponding upper trailing pressure pad in said head, for restraining said upper pad from overrunning said pusher bar. 10. A fully automatic machine as specified in claim 1 plus a pair of pressure rolls mounted in said taping zone, one in said head, extending slightly into the path of the top of a carton and having a fixed axis, and the other opposite thereto in said machine, in the path of the bottom of said carton and having a resiliently yieldable axis, the top and bottom of said carton being compressed slightly in the nip formed by said rolls when advanced therethrough to rmly seal the top and bottom stretches of said tape, and a height sensing lever arm at said folding station, depending from said head, said arm having a longitudinal extension reaching into said taping zone with the tip thereof proximate, and in advance of, said upper pressure roll, and means for maintaining said arm horizontal under the infolded side aps of a carton entering said taping zone to form a hacker member during application of the upper tape.

11. In the method of automatically sensing the dimensions of each of a plurality of random sized, erected, filled, cartons, folding in the top flaps thereof and applying moist sealing tape to the top and bottom thereof *by advancing each successive carton to a measuring and folding station and then through a moist tape applying zone of a machine, the steps of upsetting the adhesive layer on said tape into relatively tine rib and groove configuration during the moisten'- ing and feeding of the same to increase the rapidity of liquid penetration thereon,

pressing resiliently and liatwise on the tape so moistened, with a substantially constant force, during its application to the leading and trailing walls of each carton for a predetermined, prolonged period of time, as the carton advances through said zone to secure a iirm seal and a penetration of said moist adhesive into the substance of said Walls, and

relieving said pressure as the carton leaves said taping zone. 12. A method as specied in claim 11, plus the steps of passing each said carton in said taping zone through a resilient, yieldable pressure roll nip to firmly seal the top and bottom tapes thereon while said substantially constant pressure is being applied to the tape on the leading and trailing Walls thereof, and

pushing said carton through said zone by a force applied to the lower trailing Wall thereof suicient to overcome the resistance of said pressure roll nip and said leading wall tape application pressure.

13. In a fully automatic machine of the type having measuring and top flap folding mechanism at a station along a path and having moist tape applying mechanism, in a taping zone on said path, for applying tape to the leading wall, trailing wall and top and bottom walls of a carton, said machine having a single vertically movable head for operating on the top of said carton in a single pass therethrough, the combination of top and bottom leading wall pressure pads in the path of each carton advancing through said zone, each said pad having a substantially at, planar, tapeengaging face, means for moving said pads along said path while applying the said faces thereof in constant tiatwise pressure on the tape applied to the leading wall thereon, and means for moving said leading pads out of said path proximate the end of said zone, and

top and bottom trailing Wall pressure pads normally out of the path of each said carton advancing along said path, each said pad having a substantially at,

planar tape-engaging face, means for moving said pads into said path for applying the said faces thereof in constant atwise pressure on the tape applied to the trailing wall thereof and means for returning said trailing pads to said normal position when said carton leaves said zone.

14. In a fully automatic machine for closing the top flaps and for taping the top and bottom of successive, random sized erected, filled cartons,

said machine being of the type having a measuring and folding station in advance of a top and bottom tape applying zone and having a single vertically movable head extending above said station and zone for measuring carton height and operating on the top of each carton, the combination of conveyor means for advancing each said carton indvidually and successively along said path, step by step, rst to said station for measuring and for top flap folding and then along said zone for tape application, said means including means for pushing on the trailing Wall of each carton to advance the same through said taping zone,

top flap folding means on said head at said station, said means including a pivoted trailing flap folder operable in an arcuate path to infold the trailing flaps of cartons of predetermined length, carriage means supporting said folder and means for moving said carriage rearwardly of said machine, upon the arrival of a carton of excess length at said station, to cause the arcuate path of said folder to infold the trailing flap of said carton,

and substantially identical top and bottom tape applying means on said machine in said taping zone, each said means including leading wall and trailing wall substantially flat, resilient, pressure pads, means for advancing said pads, each in intimate, constant, sublstantially ilatwise pressure contact with the tape applied to one of said carton `walls for permitting said tape to secure a firm grip thereon.

References Cited UNITED STATES PATENTS 3,196,591 7/1965 Guido et al 53-137 3,236,022 2/1966 Loveland et al. 53-137 FOREIGN PATENTS 956,978 4/ 1964 Great Britain.

THERON E. CONDON, Primary Examiner NEIL ABRAMS, Assistant Examiner U.S. Cl. X.R. 

